The phenomena of aging are deepened as human beings grow older. Particularly, in the case of the skin, the change is remarkable. The main phenomena of skin aging are an increase in wrinkles, skin thickening, inelasticity, dryness, roughness, spot, etc., which are believed to be caused by skin exposure to sunlight over a long period of time. Such phenomena by sunlight are called photo-aging and are caused by the changes in epidermal and dermal tissues due to the sunlight. It has been reported that photo-aging of the skin may be alleviated when a cream containing tretinoin (all-trans-retinoic acid), retinol and derivatives thereof, AHAs, etc. are applied to the skin. However, because tretinoin is fat-soluble, it has low absorbability. Also, it is unstable in the living body, is irritant to the skin, and may cause some side-effects such as skin dryness, wounds, scraping, etc. during the latent period. Therefore, there are many problems in using tretinoin as a main component for medicines and cosmetics (U.S. Pat. No. 4,677,120). On the other hand, retinol that is vitamin A can hardly be used because it is unstable to light, oxygen, heat, lipid peroxides, or water. Therefore, in order to use retinol, additional cost should be paid for stabilizing it by anti-oxidants such as BHT, di-α-tocopherol, BHA, ascorbic acid, tocopheryl linolate, etc., or by adopting some means such as liposomes or capsules for intercepting from outside effects (U.S. Pat. Nos. 6,221,927 and 5,744,148).
Thus, there have been active studies on materials that prevent or alleviate skin aging by activating retinoic acid receptor (RAR) and also have no side effects on the skin and are safe to the skin. The present invention is a result of such studies and is based on the finding that a skin external composition containing a mixture of extracts of Lycium chinense fruits and pine needles that are natural materials has an excellent effect on the prevention of skin aging.
Up to now, this effect of a mixture of extracts of Lycium chinense fruits and pine needles has not yet been reported. The Lycium chinense fruit that is the fruit of Lycium chinense Miller is pointed at one end and pyramidal in shape, and the pericarp thereof is red or dark red in color. The outer surface thereof is crumpled, and it contains yellowish white seeds. The seeds have a flat oval shape and a diameter of about 2 mm. The Lycium chinense fruit has little or no odor, and the taste is somewhat sweet and astringent. The major pharmacological effects thereof include liver cell protection, blood pressure lowering, immune function enhancement and regulation, anti-aging, anti arteriosclerosis, female hormone-like effects, anti-tumor, blood formation stimulation, etc.
Pine needles are the needles and buds of a pine tree (Pinus sylvestris). Fresh pine needles contain large amounts of ascorbic acid and vitamin A, B and K, bitter taste compounds, flavonoids, anthocyans, 7-12% rosin, about 5% tannin, carbohydrates, essential oil (0.13-1.3 wt % in needles, 0.36% in buds, and 0.2-0.9% in one-year-old twigs), etc. In addition, the whole pine tree include components that discharge waste products (alcohol, ester, etc.) and promote metabolism, phenolic compounds, kinin, turpentine, vitamins A and C, chlorophyll-based substances, glycokinin, abietic acid, etc., and is rich in iron. It was found that red pine needles contain 24 kinds of amino acids and also 19 kinds of amino acids composed of protein. Pine needles are the source of vitamin C. Pine needles are deep green in color, and thus rich in carotene. The pharmacological effects of pine needles may be the general effects of terpene, phenolic compounds, tannin and the like, and the nutritional effects may be the effects of various nutrients and inorganic components, including fats, proteins, carbohydrates, vitamins and minerals. It was found that pine needles are rich in various mineral components, including chlorophyll vitamin A, vitamin C, vitamin P, proteins, fats, phosphorus, iron, enzymes, and essential oil, and thus exhibit an excellent effect on the removal of cholesterol. Also, pine needles contain 0.00355% calcium, 0.043% potassium, 0.2% maleic acid, 0.3198% glycine, 0.3467% serine, 0.00376% vitamin P (rutin), 0.0015% vitamin A, and 0.1301% vitamin C. In addition, pine needles are useful for the prevention of hypertension, palsy, diabetes, dementia and aging and have anticancer effects. Additionally, pine needles are beneficial for the liver and stomach, are useful for the alleviation of constipation, anemia, chronic alcoholism and hangover, nicotine removal, skin cosmetic, constitution improvement, dietaries, male stamina enhancement, and clear the head when the head feels heavy and the eyesight dims due to various stresses and excessive smoking and drinking, and thus are beneficial for students. 100 g of pine trees contain water (42.9%), crude protein (0.07%), glucose (30.6%), and natural nutrients such as minerals (K, Ca, Fe, Mg, and P) and vitamins. With respect to food nutritional components and functions, chlorophyll has hematopoietic activity (increase in hemoglobin), increases the growth of granulation tissue (regeneration of damaged tissue), activates brain cells, reduces cholesterol, and promotes the growth of tissues and cells.